Fiberoptic bronchoscopy is a commonly used clinical examination tool for the diagnosis and treatment of lower respiratory tract diseases. After the patient is under local or general anesthesia, the fiberoptic bronchoscope is usually inserted through the nostril or mouth, and is able to visualize lesions in the trachea, segmental trachea, and subsegmental bronchus, and can be used to perform biopsy sampling, bacteriological, cytological, and other investigations, as well as treatments such as alveolar lavage, cryotherapy, laser, and other therapies. Indications include: diagnosis of the etiology of unexplained chronic cough, unexplained hemoptysis or blood in sputum, pleural effusion, unexplained hoarseness, cancer cells or suspected cancer cells in sputum, and pulmonary atelectasis; and microscopic resection, freezing, and laser treatment for airway masses, and alveolar lavage for patients with alveolar protein deposition. Contraindications for bronchoscopy include: patients who are physically weak and cannot tolerate bronchoscopy, patients who are mentally abnormal and cannot cooperate with the examination, patients with chronic cardiovascular diseases, chronic respiratory diseases with severe respiratory insufficiency, etc. However, with the advancement of medical technology, the above conditions have become contraindications, and specialists will assess the condition to decide whether or not to perform bronchoscopy examination and treatment. Tracheoscopy has a wide range of indications and fewer complications, and is usually well tolerated by patients. However, tracheoscopy and treatment need to be operated by specialists.